Generally, the cause that deaf children cannot speak correctly and articulately is that they are not good at breath-control while speaking.
聋儿说不好话的原因，其共性和主要原因是发音说话不会控制气息所致。
2
And, in fact, he did make some more strides, he was a brilliant thinker, maybe he put it more articulately than those two younger scientists could have.